Which form of speciation is characterized by geographic barriers that prevent migration?

The correct form of speciation characterized by geographic barriers that prevent migration is allopatric speciation. This type of speciation occurs when a population is divided by a physical barrier, such as a mountain range, river, or other geographical feature. The separation of the population leads to reduced gene flow between the groups. Over time, the isolated populations may evolve independently through mechanisms such as natural selection, genetic drift, and mutation, eventually resulting in the formation of new species.

In allopatric speciation, the key factor is the geographic separation which allows for divergence due to the distinct environmental pressures and evolutionary pathways that each group experiences independently. This is essential in promoting the genetic and phenotypic differences that characterize new species.

The other forms of speciation, such as sympatric, parapatric, and peripatric speciation, do not primarily involve geographic barriers that completely prevent migration between groups. Sympatric speciation occurs without physical barriers, often through mechanisms like polyploidy or niche differentiation within the same geographic area. Parapatric speciation involves adjacent populations that are separated by an environmental gradient, while peripatric speciation involves a small peripheral population becoming isolated and evolving separately, often not under the same strict geographic barriers as all